Though the world of music is full of pleasure, musicians must play regularly and assiduously. A pianist for example, even an amateur, must practice almost everyday in order to keep his fingers nimble and to achieve and maintain perfect control of the keyboard.
Now, whereas a harmonica player or a violinist can carry their instrument, a pianist faces real difficulty in transporting his piano.
Of course, electronic keyboards which are easier to carry than a piano have appeared. However, existing models are still cumbersome, even though they only have a four-octave or five-octave keyboard. For example, German patent 9208106 discloses a keyboard capable of being folded in two parts, thus enabling easier transport, but the features of this keyboard (weight, size, operating mode) are still identical to those of existing keyboards that typically have only five octaves.